USING TERPOLYMERS OF PROPYLENE AND BUTYLENE WITH NUCLEATING AGENT TO FORM STERILISING FILMS OBTAINED VIA EXTRUSION BLOWING Russian patent published in 2011 - IPC C08L23/14 C08L23/20 C08J5/18 C08K5/5313 B32B27/32 B29C49/04 

FIELD: chemistry.

SUBSTANCE: invention relates to use of terpolymers of propylene/butylene/ethylene with a nucleating agent to form sterilising films obtained via extrusion blowing. A film is obtained from a polymer composition containing (i) and (ii) 0.001-1.0 wt % of one or more phosphorus-containing and/or polymeric α-nucleating agents. The terpolymer of propylene, ethylene and butylene consists of 86.0-98.0 wt % propylene, 2.0-12.0 wt % butylene and 0.1 to less than 1.0 wt % ethylene. The obtained films have a) turbidity according to ASTM D 1003-92 for a 50 mcm film less than 8% before and after steam sterilisation at 121°C for 30 minutes and b) lustre at 20° according to DIN 67530 for a 50 mcm film of at least 55% before steam sterilisation at 121°C for 30 minutes and at least 60% after steam sterilisation at 121°C for 30 minutes. The films are sterilisable and have excellent optical and mechanical properties.

EFFECT: improved method of obtaining films.

16 cl, 4 tbl, 3 ex